Zeros and logarithmic asymptotics of Sobolev orthogonal polynomials for exponential weights

• Authors: C. Díaz Mendoza;R. Orive;H. Pijeira Cabrera
• Venue: Journal of Computational and Applied Mathematics
• Year: 2009

We obtain the (contracted) weak zero asymptotics for orthogonal polynomials with respect to Sobolev inner products with exponential weights in the real semiaxis, of the form x^@ce^-^@f^(^x^), with @c0, which include as particular cases the counterparts of the so-called Freud (i.e., when @f has a polynomial growth at infinity) and Erdos (when @f grows faster than any polynomial at infinity) weights. In addition, the boundness of the distance of the zeros of these Sobolev orthogonal polynomials to the convex hull of the support and, as a consequence, a result on logarithmic asymptotics are derived.